Cisco IOS Forwarding Information Base DoS (cisco-sa-20180328-FIB-dos)

medium Nessus Plugin ID 132697

Synopsis

The remote device is missing a vendor-supplied security patch.

Description

According to its self-reported version, Cisco IOS is affected by a denial of service (DoS) vulnerability in the Forwarding Information Base code due to a limitation in the way the FIB is internally representing recursive routes. An unauthenticated, network attacker can exploit this, by injecting routes into the routing protocol that have a specific recursive pattern, provided that the attacker is in a position on the network that provides the ability to inject a number of recursive routs with a specific pattern. An exploit allows the attacker to cause an affected device to reload, creating a DoS condition.

Please see the included Cisco BIDs and Cisco Security Advisory for more information.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

Solution

Upgrade to the relevant fixed version referenced in Cisco bug ID(s) CSCva91655.

See Also

http://www.nessus.org/u?9af64740

https://bst.cloudapps.cisco.com/bugsearch/bug/CSCva91655

Plugin Details

Severity: Medium

ID: 132697

File Name: cisco-sa-20180328-FIB-dos-ios.nasl

Version: 1.10

Type: combined

Family: CISCO

Published: 1/8/2020

Updated: 3/29/2021

Configuration: Enable paranoid mode

Supported Sensors: Nessus

Risk Information

VPR

Risk Factor: Low

Score: 3.6

CVSS v2

Risk Factor: High

Base Score: 7.1

Temporal Score: 5.3

Vector: CVSS2#AV:N/AC:M/Au:N/C:N/I:N/A:C

CVSS Score Source: CVE-2018-0189

CVSS v3

Risk Factor: Medium

Base Score: 5.3

Temporal Score: 4.6

Vector: CVSS:3.0/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H

Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C

Vulnerability Information

CPE: cpe:/o:cisco:ios

Required KB Items: Host/Cisco/IOS/Version, Settings/ParanoidReport

Exploit Ease: No known exploits are available

Patch Publication Date: 3/28/2018

Vulnerability Publication Date: 3/28/2018

Reference Information

CVE: CVE-2018-0189

BID: 103548

CISCO-SA: cisco-sa-20180328-FIB-dos

CISCO-BUG-ID: CSCva91655